In the art relating to electrical connectors having a plurality of blades, usually three or more, it is well known to provide a water proof cover for protecting the connector. Examples of such are disclosed in U.S. Pat. No. 3,167,374, issued to J. F. Healy, U.S. Pat. No. 3,449,706, issued to V. L. Carissimi, and U.S. Pat. No. 3,792,415, issued to A. W. Fuller. As disclosed in these patents, the protective cover is formed from a unitary body of elastomeric material. Each of these covers merely surrounds a portion of the connector so as to protect it from the elements. In U.S. Pat. No. 3,449,706, the electrical connector blade holder, blades and electrical cable are received within the cover and are rotated relative thereto to make the connection. In U.S. Pat. Nos. 3,167,374 and 3,792,415, the cover surrounds the cable as well as a portion of the blade holder and is carried by that combination. In order to make the connection in these last two mentioned patents, the cover and the blade holder are rotated together.
These types of covers are effective for the types of connectors disclosed in these patents; however, these types of connectors have a specific drawback which requires a new type of connector and also a corresponding new type of protective cover. Specifically, these types of electrical connectors tend to come apart under certain conditions of severe vibration or the inadvertent twisting of the cable in an uncoupling direction. In order to solve this problem, a new type of electrical connector has been invented which provides a retractable locking pin adjacent one of the blades which fits into the blade receiving aperture to which connection is made. In order to retract the locking pin for unlocking purposes, the electrical connector has a rotatable actuating sleeve. A particularly advantageous form of this invention is disclosed in co-pending U.S. patent application entitled LOCKING PLUG, Ser. No. 076,792, filed Sept. 18, 1979 and now U.S. Pat. No. 4,241,969, in the names of Michael J. D'Amato and Frank C. Jaconette and assigned to the assignee of the present application. The apparatus disclosed in that application, which is hereby incorporated by reference, basically provides for a blade holder, a plurality of blades, an electrical cable connected to the blades, a generally cylindrical actuating sleeve rotatably coupled to the blade holder, a cable clamp coupled to the blade holder and clamped to the cable, and a retractable locking pin slidably received in the blade holder and protruding adjacent the side of one of the blades. The retractable locking pin is spring loaded so that, on insertion of the blades into the blade receiving apertures in a mating connector half, the locking pin is pushed into the blade holder and upon full reception of the blades in the apertures and rotation thereof the locking pin is biased into one of the apertures next to the blade. This fills the aperture and prevents rotation of the blade and therefore inadvertent removal. In order to withdraw the locking pin, the actuating sleeve is rotated relative to the blade holder which draws the locking pin into the blade holder. Continued rotation of the actuating sleeve moves the blade into a position in which they may be pulled out of the apertures.
In order to provide an effective weather proof cover for this new electrical connector or for any locking connector having a rotatable actuating sleeve, the cover must be torsionally flexible about the longitudinal axis of the blade holder and the electrical cable so as to absorb rotation thereof upon gripping and rotation of the actuating sleeve. In addition, this cover must be effective in all types of weather in both low and high temperatures. None of the three patents set forth above provide for such a required torsional flexibility since they are not constructed to deal with this type of movement. Similarly, U.S. Pat. No. 3,157,450, issued to W. B. Harrison, Sr. et al., while disclosing an electrical cable connector with a cover and a clamping assembly, fails to disclose the concept of providing significant torsional flexibility.